no...definitely NOT slang for 'sexy'!!!!!! it means you don't have an a_s...means your a_s is bony... when you tell someone i'm gonna kick your scrawny butt, you're not saying that their butt is "literally" scrawny. you're just saying "I'm tuff stuff and if you don't mind your p's and q's, then you're gonna a footprint on your backside!" so there! :)